[[managed_properties]]
== Using Gradle Managed Properties

Gradle's managed properties allow you to declare properties as abstract getters (Java, Groovy) or abstract properties (Kotlin).

Gradle then automatically provides the implementation for these properties, managing their state.

A property may be _mutable_, meaning that it has both a `get()` method and `set()` method:

                      description: Traffic policies that apply to this subset.
                      properties:
                        connectionPool:
                          properties:
                            http:
                              description: HTTP connection pool settings.
                              properties:
                                h2UpgradePolicy:
                                  description: |-

/**
 * An immutable view of all properties available for build options, calculated from command-line options, the environment and the various
 * properties files.
 */
public interface AllProperties {
    /**
     * Returns the system properties defined as command-line options.
     */
    Map<String, String> getRequestedSystemProperties();

    /**

    def "writes expected properties into file"() {
        when:
        UpdateDaemonJvmModifier.updateJvmCriteria(daemonJvmPropertiesFile, JavaVersion.VERSION_11, JvmVendor.fromString("IBM"), JvmImplementation.VENDOR_SPECIFIC)
        then:
        def props = daemonJvmPropertiesFile.properties
        props[DaemonJvmPropertiesDefaults.TOOLCHAIN_VERSION_PROPERTY] == "11"

            tasks.register('printSystemProperty') {
                doLast {
                    System.properties.each { k, v ->
                        println("$k=$v")
                    }
                }
            }
        '''
    }

    @TargetGradleVersion(">=3.0 <7.6")
    def "Custom system properties are ignored in older Gradle versions"() {
        setup:

    /**
     * Gets the system properties to use for interpolation and profile activation. The system properties are collected
     * from the runtime environment like {@link System#getProperties()} and environment variables.
     *
     * @return The execution properties, never {@code null}.
     */
    Map<String, String> getSystemProperties();

    /**

    }

    File createModule(String simpleName, Properties properties) {
        def moduleDir = tmpDir.createDir("$simpleName/build/resources/main")
        save(properties, moduleDir.file("gradle-$simpleName-classpath.properties"))
        moduleDir
    }

    private Properties properties(Map kvs = [:]) {
        new Properties().with {
            putAll(kvs)
            it
        }
    }

 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.gradle.internal.properties.annotations;

import com.google.common.collect.ImmutableSet;
import org.gradle.internal.properties.PropertyValue;
import org.gradle.internal.properties.PropertyVisitor;
import org.gradle.internal.reflect.validation.TypeValidationContext;
import org.gradle.internal.service.scopes.Scope;

	}

	for k, vFld := range v.Properties {
		if sFld, ok := s.Properties[k]; !ok {
			if sAdditionalPropertiesSchema == nil || !opts.AllowValidationPropertiesWithAdditionalProperties {
				allErrs = append(allErrs, field.Required(sPath.Child("properties").Key(k), fmt.Sprintf("because it is defined in %s", vPath.Child("properties").Key(k))))
			} else {
				// Allow validations on specific properties if there exists an

[[sec:project_properties]]
== Project properties

Project properties are available on the link:{groovyDslPath}/org.gradle.api.Project.html[Project] object.
They can be set from the command line using the `-P` / `--project-prop` <<command_line_interface.adoc#sec:environment_options, environment option>>.

The following examples demonstrate how to set project properties in different ways.